We'll start with really astonishing twist in a murder mystery that terrified an entire neighbor. Police found a couple tied up in their home in Texas, the husband was stabbed to death. Investigators spent a year and a half searching for the killer. But now it turns out their suspect was right under their nose. ABC's Gloria Riviera is here with more. Good morning. Good morning, Dan, bianna. This case did not sit well with investigators from the start. A break-in but nothing stolen. A couple found one dead one alive with no explanation from the survivor. Now they think they know why. We've been scared for quite a while. Reporter: It is a shocking twist to a murder that shook this Houston neighborhood almost two years ago. 54-year-old Sandra millgar originally believe be to a victim. Her husband killed. She's been charged with his murder. It was Christmas eve 201, Sandra and Jamie planning to celebrate their 32nd wedding anniversary. Relatives on their way to that celebration discovered the couple tied up in separate closets. Jamie fatally wounded. She says they were in the bathroom together. Her and her husband and that sometime she blacked out and next thing she remembers is waking up in 9 closet tied up. But it was all an elaborate lie. Documents alleging service Sandra who stabbed Jamie with a knife. Is seemed strange with how it came down with them being tied up and just one person being killed. Reporter: It's not clear what information led authorities to arrest Melgar but some in this community already feel better knowing it might not have been a random break-in with deadly consequences. I'm relieved to know it's not random -- not a home invasion. Reporter: Sandra posted out of jail on a $50,000 bail and is due in court in a few weeks. The melgars were described as a model communiuple. The community eagle story hear on what her motive might have been. August 14th it'll happen. I remember covering that story. Great to see you on set. Thank you. Now let's get an update of

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